• Korean Journal of Agricultural Science
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• v.13 no.1
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• pp.1-16
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• 1986

This experiment was carried out to obtain genetic information for future corn breeding. The materials used for the study were obtained from the nationwide collection of Korean local corn lines. A total of 262 lines were used for the study of morphological characters and for the classification of lines. Results obtained are summarized as follows; 1. The days to flowering of lines ranged from 57 days to 87 days. Most lines had an average of 67 days of flowering days. 2. The number of tillers of lines showed a lot of variation among lines with 49.2% of coefficient of variation. 3. The coefficients of variation computed based on the phenotypic observation or measurement of each line were 36.1%, 27.2%, 20.0%, 16.4% and 16.3% for kernel weight per ear, 100 kernel weight, ear height, plant height and ear length, respectively. 4. Ear height, ear length, ear diameter, tiller number and days to flowering were highly and positively correlation with the plant height. Kernel size, ear size, and plant height were highly correlated with 100 kernel weight and kernel weight per ear. 5. The 262 corn lines were possibly classified into four major groups by the Euclidean distance. Group I comprised 110 lines, group II 74 lines, group III 66 lines and group IV 12 lines, respectively. Group I was characterized as having early maturity, medium plant height large kernel size and large ear size. Group II had medium maturity, short plant height, medium kernel size and small ear size. Group III had medium maturity, medium plant height, large kernel size and medium ear size. Group IV had late maturity, long plant height, small kernel size, small ear size and many tillering. 6. The plant height showed significant difference between group I and II, II and III, and II and IV group. No statistical differences were observed between group III and IV. The ear size of group I was significantly different from those of group II, III and IV. Also difference of ear size between group II and III was significant. The kernel size, 100 kernel weight and kernel weight per ear were all significantly different among all groups classified. The row number was different between group I and II. The row number of lines in group IV was significantly different with group I, II, III respectively. The number of tillers and flowering days of lines in group IV were greatly different from those of group I, II and III. 7. The corn lines collected from northwest plain regions and middle hilly regions in Korea had medium maturity, medium plant height, large ear and large kernels. The corn lines from middle eastern hilly regions had medium size of ear kernels. The corn lines from middle southern hilly regions had late maturity, small kernel size and many tillers. The corn lines from southwest plain areas had late maturity, long plant height and many tillers.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.1
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• pp.92-96
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• 1987

A sweet corn hybrid. ‘Golden Elite 70’ was grown at four plant densities of 4.500, 5.500, 6,500 and 7,500 plants per 10 ares under early and ordinary season cultivations, respectively, to determine effects of plant density on growth and yield of sweet corn. Plant and ear heights and ear size were greater, and ear number per plant was less at ordinary season cultivation compared to early season cultivation. However. ear weight per 10 ares were similar between two cultural practices. There were no significant interactions between cultural practice and plant density for plant height, yield and yield components except ear length. Plant density did not affect silking date, and plant and ear heights and did not show consistent trend in ear size. Ear number per plant decreased with increasing plant density. Ear number and weight per 10 ares increased as plant density increased up to 6,500 plants per 10 ares and tended to decrease at 7,500 plants per 10 ares. The results indicate that the optimum plant density for sweet corn would be around 6,500 plants per 10 ares.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.1
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• pp.1-8
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• 2010

Few management studies have been conducted on late planting date for corn silage in paddy field as a barley-corn forage cropping system. Experiments were conducted during 2007 and 2008 at the Chungnam Agricultural Research & Extension Services. The objectives of this study were to determine relationships between planting date and com forage yield and to determine the best hybrid at the delayed planting after whole crop barley's harvest. The treatments consisted of 2 planting dates and 7 hybrids. Delayed planting considerately reduced stem diameter, individual ear size and weight. The ratio of dried leaf and culm in aerial plants was increased and that of ear was decreased. The coefficient of variation in fresh, dry matter (DM) and total digestible nutrients (TDN) yield was higher at delayed planting date on cropping system with whole crop barley than that of planting at optimum season. So, fresh weight was reduced by 91.8%, dry matter by 72.6%, grain yield by 51.0% and TDN yield by 68.1%. The appropriate hybrid for delayed planting after whole crop barley harvest in middle region was 'Gangdaok' as lower in the reduction of ear size and weight compared to that of planting at optimum season. Reduction in grain yield caused to decrease the DM and TDN yields. Therefore, to gain stable dry matter in silage corn by delayed planting date on cropping system with whole crop barley was necessary to select com hybrid on the minimum reduction in ear size and weight.

• Korean Journal of Agricultural Science
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• v.4 no.2
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• pp.215-228
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• 1977

In order to provide good germplasm for developing good corn hybrids, a total of 948 Korean indigenous corn lines were collected from various parts of country and major morphological characterstics of ears were investigated. The results obtained were as follows; 1) Ear Type; From the east-north mountaionus region where more than 80% of total corn production is practiced, cylinder (type I) or similar types to cylinder corn were collected, and from the southern plain region, where rather small scales of corn is grown, cone type (type IV) or similar types to cone were prevalent. 2) Kernel color; In the ear colors of all the indigenous corn lines collected from ten regions, ears with mono color were 54.4%, ears with two color mixed were 39.0% and ears with three or more color mixed were 6.6%. In northern mountainous region, region A and region I, ear color was mostly white or white plus other colors, while in other regions ear color was yellow or yellow plus other colors. 3) Denting; Dent type was only 4.3% of Korean indigenous corn lines collected, and others were flint type. Dent type was collected from northern regions, where foreign corn varieties were introduced and grown. 4) Ear row number; Ear row numbers of indigenous corn lines collected were 12 to 16. There was no significant differences among the ear row numbers in a ear ciassified by regions. However, it was observed that ear row number was closely related to kernel size. For instance, the ears with 24 ear-rows were the smallest in kernel size. 5) Quality of starch; 70.9% of the indigenous corn lines collected were kernels with hard starch. Corn with soft starch was 26.0% and medium type was 3.1%. In region A and region I, where lot of corn is grown, corn with hard starch was more frequently collected. 6) Pop corn and waxy corn; In all the indigenous corn lines collected, popcorn was distributed uniformly through the regions except region I, and waxy corn was found more in the northern mountainous region. 7) Ear length; The mean ear length of indigenous corn lines collected was 13cm. In region A and region I ear length was larger than that in other regions. 8) Ear diameter; The mean ear diameter of indigenous corn lines collected was 3.3cm. In region A and region I ear diameter was larger than that in other regions. 9) Kernel length, kernel width and kernel thickness; The mean kernel length, kernel width and kernel thickness of indigenous corn lines collected were 0.82cm, 0.42cm, and 0.78cm, respectively. The kernel size in the region A and region I was larger than that in other regions. 10) Ear weight; The mean ear weight of indigenous corn lines collected was 58.04gr. Ear weight was remarkably heavier in region A and region I. The heaviest ear weighed 330gr, and the lightest ear weighed 5 gr. 11) Kernel weight of a ear and 100 kernel weight; Kernel weight of a ear and 100 kernel of indigenous corn lines collected were 47.07gr and 15.07gr, respectively. Kernel weights and 100 kernel weights were much heavier in region A and region I than other regions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.2
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• pp.140-145
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• 1985

Field experiments were conducted in Suwon in 1982 and 1983 to evaluate the effects of compost application, nitrogen (N) rate and split application of N on growth, yield and N uptake of sweet corn (Zea mays L.) grown under clear polyethylene mulching condition. Urea was banded at N rates of 0 (only in 1983), 5, 10, 15 and 20 kg per 10a with or without compost application of 1500 kg per 10a at planting. In 1982, half of N was sidedressed at the 5-6 leaf stage in case of 15, and 20 kg N per 10a. Compost application increased ear size and ear weight per 10a (10%). The number of ears per 10a markedly increased with an increase in N rates up to 10 kg per 10a but was not significantly affected by further increased N rates. Ear weight per 10a increased linearly as N rate increased from 0 to 20 kg per 10a without compost but increased greatly up to 10 kg N per 10a with compost application. Dry matter yield increased greatly up to 15, 10 kg N per 10a with and without compost application, respectively. Nitrogen uptake increased linearly from 8.1 to 18.8 kg per 10a with an increase in N rates from 0 to 20 kg per 10a. The optimum N rate appeared to be 10 to 15 kg per 10a based on ear number, ear weight and dry weight per 10a. There was no significant difference between basal and split applications of N in terms of ear size, and number and weight of ears per 10a.

• IE interfaces
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• v.13 no.2
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• pp.147-156
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• 2000

It is known that the human stature and its related dimensions generally increase until the late teens or early twenties, remain relatively constant throughout early adulthood, and decline from early-to-middle adulthood into old age. However, there is exception that the length of the human ears, which continue to grow throughout life. In this study, 600 Korean male and female subjects aging from 17 to 89 were selected. Four different points of external ears including Pinna length, ear connection point length, Concha length, and Lobule thickness were measured along with other relative subjects' demographic data(e.g., age, stature, weight) to determine the relationship among these obtained data. The results showed that the age, sex, and different ethnic populations were functions of ear dimensions similar to the human stature. For example, the Pinna length increases as the age increases(r= 0.689, p<0.00l). The primary objective of this study was thus to provide anthropometric dimensions of Korean ear for the product designers and recommend the appropriate product design solutions in relation to human ear. Based on the results of this study, it is suggested that the continuing growth of the human body parts should be considered in the application of anthropometric data to the design of the things especially for human use.

• Archives of Craniofacial Surgery
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• v.18 no.3
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• pp.155-161
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• 2017

Background: Because of the relatively similar size of organs to human and the physiological and structural similarities, the use of porcine as xenograft donors is progressing very actively. In this study, we analyzed the characteristics of porcine ear cartilage and evaluated its suitability as graft material in reconstructive and cosmetic surgery. Methods: The auricular cartilage was harvested from two pigs, and subjected to histological examination by immunohistochemical staining. To determine the collagen content, samples were treated with collagenase and weight changes were measured. After sterilization by irradiation, the samples were grafted into rats and stained with Hematoxylin and Eosin and Masson Trichrome to observe inflammation and xenograft rejection. Results: In IHC staining, extracellular matrices were mainly stained with type II collagen (20.69%), keratin sulfate (10.20%), chondroitin sulfate (2.62%), and hyaluronic acid (0.84%). After collagenase treatment, the weight decreased by 68.3%, indicating that about 70% of the porcine ear cartilage was composed of collagen. Upon xenograft of the sterilized cartilages in rats, inflammatory cells were observed for up to 2 months. However, they gradually decreased, and inflammation and reject-response were rarely observed at 5 months. Conclusion: The porcine ear cartilage was covered with perichondrium and cellular constituents were found to be composed of chondrocytes and chondroblasts. In addition, the extracellular matrices were mainly composed of collagen. Upon xenograft of irradiated cartilage into rats, there was no specific inflammatory reaction around the transplanted cartilage. These findings suggest that porcine ear cartilage could be a useful alternative implant material for human cosmetic surgery.

• Korean Journal of Agricultural Science
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• v.9 no.1
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• pp.396-450
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• 1982

To obtain basic information on the Korean local corn lines a total of 57 lines were selected from 1,000 Korean local collection at Chungnam National University, classified by principal component analysis, and genetic nature was investigated. The results are summarized as follows. 1. There were a great variation in mean values of plant characters of the lines. The mean values of plant characters except for density of kernels varied with types of crossing. All characters except. for tasselling dates were reduced in magnitude when selfed, while those characters were increased when topcrossed. 2. The correlation coefficients among characters studied ranged front 0.99 to -0.59. The correlation coefficients among characters were not greatly changed depending upon types of crosses. 3. In order to classify the lines more effectively, selected 12 plant characters were used to classify 57 local lines by principal component analysis. The first four component could explain 86.4%, 83.4% and 81.1% of the total variations in sibbed lines, selfed lines and topcrossed lines, respectively. 4. Contribution of characters to principal component was high at upper principal components and low at lower principal components. 5. Biological meaning of the principal component and plant types corresponding to the each principal component were explained clearly by the correlation coefficient between principal components and characters. The first principal component appeared to correspond to the size of plant and ear. The second principal component appeared to correspond to the degree of differentiation in organs and the duration of vegetative growing period. But biological meaning of the third and fourth principal components was not clear. 6. The lines were classified into 4 lineal groups by the taxonomic distance. Group I included 52 lines which was 91.2% of total lines, group II 3 lines, group III 1 lines and group IV I lines, respectively. Four groups could be characterized as follows : Group I : early maturity, short-culmed, medium height plant, small ears, medium kernels and medium yielding. Group II : late maturity, medium height plant, small ears, small kernels, prolific ears and higher yielding. Group III : medium maturity, tall-culmed, small ears, small kernels and low yielding. Group IV : medium maturity, tall-calmed, large ears, one ear plant and me yielding. 7. The inbreeding depression varied with plant characters and lines. The characters such as yield, kernel weight per ear, ear weight and plant height showed great degree of inbreeding depression. Group I showed high inbreeding depression in such characters as 100 kernel weight, leaf number, plant height and days to tasselling, while group II showed high inbreeding depression in other plant characters. 8. Heterosis of plant characters varied also with lines. The ear weight, kernel weight per ear, yield, 100 kernel weight, and plant height were some of the plant characters showing high heterosis. Group II showed high values of heterosis in such characters as ear length, ear diameter, ear weight, kernel weight per ear, 100 kernel weight, and leaf length, while group I was high in heterosis in other plant characters. 9. The degree of homozgosity was highest in ear weight (79.1%) and lowest in ear number per plant (-21%). Group II showed higher degree of homozygosity than group I. 10. Correlation coefficients between characters of ribbed and topcrossed lines were positive for all characters. Highly significant. correlation coefficients between ribbed and topcrossed lines were obtained especially for characters such as ear number per plant, plant height, leaf length and yield per plot.

• The Korean Journal of Food And Nutrition
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• v.32 no.6
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• pp.620-629
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• 2019

To examine the possibility of ear mushroom (EM) as a source of natural vitamin D, the UVB (ultraviolet B) was treated according to sample drying status, drying methods before UVB treatment and harvest time. And then, vitamin D₂ and ergosterol contents were investigated. According to the sample drying status, the vitamin D₂ contents of fresh and freeze-dried EM (whole) increased to 4,634.4~4,780.9 ㎍/100 g D.W. (dry weight) under UVB dose 52.5~70.0 kJ/㎡ and above 18,693.1 ㎍/100 g D.W. under above 105 kJ/㎡, respectively. By drying methods before UVB treatment, vitamin D₂ contents of EM powder (below 500 ㎛) that dried in the vinyl house and freeze-dryer increased to 4,886.2~5,132.9 ㎍/100 g D.W. under above 105 kJ/㎡ and 17,103.7 ㎍/100 g D.W. under 70 kJ/㎡, respectively. Ergosterol content decreased with increasing UVB dose in all experiments. According to the harvest time, vitamin D₂ content under UVB dose 210 kJ/㎡ showed marked difference and in order of June, July, August, October and April. As for the results, the optimum harvest time, drying method before UVB treatment, sample size, UVB dose for the EM contained high vitamin D₂ content were June, freeze-drying, whole, and 105 kJ/㎡, respectively.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.88-88
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• 2017

The study was conducted to analyze the growth characteristics comparison per planting density on the waxy corn early-planting culture for the paddy field in the southern province of south Korea. The cultivation period of early-planting culture for the paddy farming of the waxy corn are sown on February 15, 2016years, transplanting March 15 and harvest June 20. And it grew 126 days. The weather change according to the cultivation period of unheated plastic house early-planting culture, it was average temperature $14.6^{\circ}C$ and humidity 62.5%. And the temperature was 5.6 degrees Celsius warmer compared with the outside temperature and the humidity was 0.7 percent higher tendency. At the growth per planting density of waxy corn, culm length was average 224cm, the more it is high density culture the more was high trend. Stem diameter and ear length the more it is high density culture the more was lowed trend. The node number of $60{\times}20Cm$ was 12 nodes, fruit seting 5.7 nodes, tasseling number 94 days and silking number 96 days. In the ear characteristics per planting density, the size of ear length, seed setting length, ear width and ear weight the more planting density is high the more lowed that trend. The commodity percentage of planting density $60{\times}35Cm$ was the highest among other treatment as 69.1%. But, marketable yield was the highest planting density of $60{\times}20Cm$ as 4,543 ears/10a, and appeared in order $60{\times}25Cm$ 95%> $60{\times}30Cm$ 93%> $60{\times}35Cm$ 92%. The planting density on the waxy corn early-planting culture for the paddy farming in the southern province, the planting density analyzed to be effective planting of over 25% than normal season culture.